Many known TV and video standards, such as NTSC, utilize interlacing for video coding. For example, odd or even lines of an image are drawn on the screen alternatively for every 60th of a second, with each line being updated at a frame rate of 30 frames per second. One reason is that traditional, long established display devices such as CRT televisions could not support high refresh rate for full frame. Through video interlacing, flickering can be reduced due to persistence of vision effect while the vertical resolution can be maintained.
In modern display devices that do not support display of interlaced video, such as LCD display types, de-interlacing has to be applied to interlaced video to obtain the missing lines in each of the odd line and even line frames by interpolation.